and again the advantage to writing it in scientific notation is immediately obvious. In this case the coefficient is 9.10956 (we know this mass more precisely, to more digits, than we know the distance to the Andromeda galaxy) and the exponent is -31. A negative exponent is the same as dividing by 10 this many times. Another way to say this is we have to shift the decimal point 31 places to the right to convert the number to the coefficient.